“I know the evidence against Alex Rodriguez, and I will tell you this — it will never stand up in a court of law or in an arbitration panel courtroom. Never. Because the evidence is based on one person — Anthony Bosch,” attorney Joe Tacopina told Matt Lauer.

Bosch was the head of Biogenesis of America, a shuttled Florida anti-aging clinic accused of distributing banned performance-enhancing drugs to numerous players, including Rodriguez. Rodriguez was suspended through the 2014 season on Aug. 5 when the league penalized 13 players following its probe into Biogenesis.

He contintues to play for the New York Yankees as the appeals process unfolds.

Bosch “has no credibility,” Tacopina said, because MLB made a deal with Bosch and offered to pay his legal fees.

“And more importantly, he has no ability to testify because he is someone who has peddled drugs to high school students,’’ Tacopina said.

But Bosch says A-Rod once helped pay his legal expenses.

“Bosch retained the legal services of Susy Ribero-Ayala in February 2013. A retainer was paid (via wire transfer) by a representative of Alex Rodriguez. Ms. Susy Ribero-Ayala accepted this payment on behalf of Anthony Bosch as payment for his legal representation,” Bosch spokesperson Joyce Fitzpatrick told NBC News.

That led to an interesting exchance when Lauer asked Tacopina why Rodriguez would help with Bosch's legal bills if he lacks credibility. The attorney said he could not discuss the issue due to the confidentiality clause of MLB’s Joint Drug Prevention and Treatment Program.

But Lauer said the program had a received a letter from MLB.

“They sent us a letter saying that if you’re willing to sign this letter, that they are willing to waive the confidentiality clause in the Joint Drug and Prevention Program, that they’ll be allowed to talk about everything and you’ll be allowed to talk about everything. They said that would include all prior violations of the program committed by Rodriguez, all documents, records, communications, text messages and instant messages related to Rodriguez’s treatment by Anthony Bosch.”

Tacopina said he would review the letter.

“We would love nothing more than to be able to discuss the testing history and the scientific evidence and the test of Alex Rodriguez regarding this JDA,’’ Tacopina said.